This invention relates generally to glow plugs in engine cylinder heads in internal combustion engines. More particularly, this invention relates to a glow plug connection device for use in an internal combustion engine having a rocker carrier.
BACKGROUND OF THE INVENTION
Internal combustion engines commonly employ cold start devices, such as a glow plug, to assist in ignition. Existing engine designs commonly have glow plugs located inside the engine valve cover. A glow plug, shown in FIG. 9, is generally used to preheat the combustion chamber mixture of a diesel engine, or an auto-ignition internal combustion engine, to assist in cold starting. The single glow plug corresponding to a combustion chamber is generally secured to or installed in the cylinder head of the engine such that there is an equal number of combustion chambers and glow plugs. For example in a diesel engine with a V-8 configuration, there will be a total of eight glow plugs with four glow plugs on each cylinder bank.
Each glow plug is typically electronically connected to a power source via a single glow plug connector attached to an under-valve cover wire harness. The under-cover valve cover wire harness is then appropriately electronically connected to an external engine harness which is in turn connected to an engine power source. The interface between under-valve cover and external harnesses provides a sealing function that prevents engine oil leakage. In the interior of the valve cover, the glow plug connectors, attached to the under-valve cover wire harness, are individually connected to corresponding glow plugs. This often times leads to crowding of engine components in the limited space under the valve cover. Also, the installation of each glow plug connector individually to each glow plug terminal results in increased manufacturing time and costs.
Further, mounting existing wire harness glow plug connectors individually to the glow plugs can be difficult, time consuming and requires some force to push and connect the wire harness connectors to the glow plug terminals. The wire harness connectors can be connected manually or with special insertion tools. Due to the limited space under the valve cover, it is difficult to individually install glow plug connectors properly to corresponding glow plug terminals. Many times, the resultant electrical connection between the glow plug connector and the glow plug terminal is many times not secure and electrically inadequate. As a result electrical testing is normally required to verify that there is adequate electrical contact between the glow plug connector and the glow plug terminal. The required testing is a drawback that also leads to increased engine manufacturing time and cost.
Accordingly, there is a need for a glow plug connection apparatus that is easy to install, prevents engine oil leaks and results in a consistently good electrical connection between the glow plug connector and glow plug thereby reducing engine manufacturing time and costs.
The present invention provides a glow plug connection apparatus for electrically connecting to a plurality of glow plugs while simultaneously sealing the engine from oil leakage. The glow plug connection apparatus simultaneously installs a plurality of glow plug connectors to corresponding glow plugs mounted in a cylinder head in an internal combustion engine. The glow plug connection apparatus comprises, a rigid buss bar rail, a plurality of glow plug connectors attached to the rigid buss bar rail, a plurality of connector wires routed in the rigid buss bar rail and electrically connected to corresponding glow plug connectors, a wire router, and a conduit retaining clip between the wire router and the rigid buss bar rail. The rigid buss bar rail and the glow plug connectors preferably form an apparatus connector angle. The glow plug connector wires can terminate in a multi-port glow plug wire connector or a single connection point.
Additionally, the glow plug connector of the glow plug connection apparatus preferably comprises a buss bar rail interface section, a sealing section having an O-ring seal able to seal the glow plug connector to a glow plug passage, a guide section having a plurality of guide fins around the periphery of the glow plug connector, and a clip section having a plurality of clip fingers around the periphery of the glow plug connector able to engage a glow plug terminal. In a preferred embodiment, at least one the clip fingers has a protruding lip. The buss bar rail interface section and the glow plug connector body preferably form a glow plug connector angle.
The following drawings and description set forth additional advantages and benefits of the invention. More advantages and benefits are obvious from the description and may be learned by practice of the invention.